Hello how add Drawerhost OnOpen/OnClose event like dialoghost DialogOpenedEventHandler/DialogClosingEventHandler

I believe the following code should be moved to ColorHelpers.h

https://github.com/microsoft/microsoft-ui-xaml/blob/986d48adaccaabd569dab76137543b1102b24b6c/dev/ColorPicker/ColorHelpers.cpp#L11-L18

What would you like clarification on:

I read that Uno renders all controls in Windows style and there is an option somewhere deep in Uno to have some of the controls render in native OS style.

I believe it's crucial to be able to switch an application's (or page's) property to render controls using native styles wherever applicable (and to be able to switch back to Windows style again when

Describe the bug
Currently Files UWP doesn't work properly in high contrast themes and there are a lot of issues.

To Reproduce
Steps to reproduce the behavior:

1. Switch to any high-contrast theme
2. Open and use Files UWP
3. You'll notice that the design is inconsistent and worse

Expected behavior
App should look like any other app in high contrast themes.

**Screenshots